When drip flow drops, delivery becomes uneven or emitters clog, first distinguish problems in the filtration stage, distribution network and emitters. Media filtration, disc filtration and RO perform different tasks. Conventional irrigation filtration retains particles within its specified range; it must not be presented as removing dissolved salts. Obtain water-source information and emitter requirements before selecting the filtration method.
| Type | Main function to consider | Purchasing checks |
|---|---|---|
| Sand / media filtration | Water passes through a media bed that retains suspended impurities | Feedwater impurities, media grading, bed configuration, water distribution and backwash supply |
| Disc filtration | Water is filtered through the grooved passages of compressed discs | The specified filtration rating, permitted flow, pressure loss and cleaning conditions |
| Screen filtration | Water passes through a screen that retains particles within its specified range | Screen opening size and rating definition, effective area, differential pressure and cleaning requirements |
Water clarity alone cannot determine which filter is suitable
First obtain the emitter manufacturer's filtration requirements and confirm the units and definition of the filtration rating. Then check suspended solids, sediment or organic impurities in the source water, system flow and maintenance conditions. Some designs use two filtration stages: the first handles the main impurity load, and the second meets the emitter requirements. The need for two stages and the combination selected should follow actual water-source data and the relevant equipment documentation.
The absence of visible particles does not mean that no treatment is needed. Problems caused by dissolved salts, chemical deposits or biological factors cannot be considered resolved simply by changing a particle filter. A high EC reading alone is also not a basis for adding EDI.
| Observation point | Records to retain | Intended use |
|---|---|---|
| Water source and filter inlet | Changes in the water source, operating periods, inlet pressure and flow | Check whether conditions entering the filtration stage have changed |
| Filter outlet | Outlet pressure, differential pressure under comparable conditions, and records before and after cleaning | Observe filtration resistance and recovery after cleaning |
| Irrigation zones and end points | Affected locations, active zones, end-point pressures and observed discharge | Distinguish supply issues from differences between locations and provide context for diagnosis |
| Fertilizer dosing stage | Product and mixing records, operating times and recent changes | Have irrigation and growing personnel review compatibility and management conditions together |
If problems persist after backwashing, start with the records
Compare filter differential pressure before and after cleaning at comparable flows. If recovery differs from the normal baseline, collect records of the backwash supply, drainage route, valve operation, and media or disc maintenance. Follow the equipment instructions for the sequence of work and shutdown conditions. Never open a pressurized housing; electrical, pressure-system and chemical work should be handled by appropriately qualified personnel.
When contacting Gudian, provide the water-source report, complete filter and emitter model numbers, zone water requirements and issue records. These help identify missing information and the treatment stage to review next.
Related resources and next steps
- Fertigation equipment and responsibilities
- Illustrative fertigation equipment configurations
- Existing-system information for retrofit planning
Sources and scope
Drafted with AI assistance on 8 October 2026 and checked item by item against the knowledge base and the public sources below. Manufacturer information explains the relevant technology; it does not imply that Gudian is an authorized distributor or manufacturer for that brand. Equipment specifications are subject to the selected model and confirmed documents.